Founder Sam Lessin will be joining Facebook full time. Drop.io's service, meanwhile, will be shutting down, making this yet another "acqui-hire" on Facebook's behalf--buy a start-up primarily for its founder, and put that new hire to work developing a new feature at Facebook or improving an old one.

"In the coming weeks, we'll be winding down the drop.io service. As of this week, people will no longer be able to create new free drops, but you'll be able to download content from existing drops until Dec. 15," the post on Drop.io's blog explained. "Paid user accounts will still be available through Dec. 15 and paid users will be able to continue using the service normally. After Dec. 15, paid accounts will be discontinued as well."

Facebook's ties to Drop.io run deep. Lessin had attended Harvard University along with Facebook founder Mark Zuckerberg, and David Kirkpatrick's book "The Facebook Effect" describes him as a crucial player in Facebook's early days: "At the end of the (spring 2004) semester, Lessin, whose father was a well-known investor, took Zuckerberg around New York to meet with venture capitalists and executives in the finance and media industries," Kirkpatrick describes on page 41 of the exhaustive Facebook biography.

Lessin had also, sources say, been an instrumental dealmaker in Facebook's acquisition of Hot Potato, a mobile "check-in" service that it bought earlier this year and in which Lessin had been an angel investor. Similarly, Hot Potato had shut down and Shaffer joined Facebook, where earlier this month he unveiled its new Groups product.

Facebook confirmed to CNET that Lessin will switch coasts and move to Facebook's main headquarters in Palo Alto, Calif., as Shaffer did.

"We can confirm that we recently completed a small talent acquisition for Drop.io and acquired most of the company's assets," a statement from Facebook read. "We're thrilled that Sam Lessin will be joining us at Facebook."

A price for the acquisition of Drop.io, which had raised a round of Series A venture capital from RRE Ventures and DFJ Gotham, wasn't disclosed.

About the author

Caroline McCarthy, a CNET News staff writer, is a downtown Manhattanite happily addicted to social-media tools and restaurant blogs. Her pre-CNET resume includes interning at an IT security firm and brewing cappuccinos.
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